If you want the glass material to fill in the material of the surface of the pressure gauge If the glass is easy to use paint etc. If it is easy to do with thinner but PVC etc. it will melt into thinner and disappear

Measuring error is large because the pressure range of the pressure gauge of the air chuck gun is large. So replace it with a small pressure gauge. Somewhat, good. A little more, the pressure gauge, the larger one is still better.

I used a pressure gauge of 1.0 MPa to adjust the air pressure of the airbrush up to now, but a fine scale is required for fine adjustment, I have purchased this 0.25 MPa purchased. I am very satisfied that the air pressure can be measured steadily without blurring of the needle. I am pleased to purchase at this price.